A lignan compound, P3, having strong antioxidative activity was found to be formed in high concentration during the industrial bleaching process of unroasted sesame seed oil. P3 (named sesaminol) was identical to a minor constituent previously isolated from acetone extract of sesame seed. It was shown that sesamolin in unprocessed sesame oil is the source of seaseminol, and the formation of seasaminol was confirmed by the model experiment with corn oil to which sesamolin had been added. Sesaminol was not so greatly removed by the deodorization process that follows bleaching as was sesamol, and it was shown to be at a concentration of ca. 100 mg/100g in commercial refined unroasted seed oil. The antioxidative activity of sesaminol was foughly equal to those of sesamol and γ‐tocopherol by the thiocyanate method. Therefore, it seems that the antionxidative activity of refined unroasted seed oil is mainly attributed to sesaminol.

Crop leaves are subject to continually changing light levels in the field. Photosynthetic efficiency of a crop canopy and productivity will depend significantly on how quickly a leaf can acclimate to a change. One measure of speed of response is the rate of photosynthesis increase toward its steady state on transition from low to high light. This rate was measured for seven genotypes of soybean [Glycine max (L.) Merr.]. After 10 min of illumination, cultivar 'UA4805' (UA) had achieved a leaf photosynthetic rate (Pn ) of 23.2 μmol · m(-2)  · s(-1) , close to its steady-state rate, while the slowest cultivar 'Tachinagaha' (Tc) had only reached 13.0 μmol · m(-2)  · s(-1) and was still many minutes from obtaining steady state. This difference was further investigated by examining induction at a range of carbon dioxide concentrations. Applying a biochemical model of limitations to photosynthesis to the responses of Pn to intercellular CO2 concentration (Ci ), it was found that the speed of apparent in vivo activation of ribulose-1:5-bisphosphate carboxylase/oxygenase (Rubisco) was responsible for this difference. Sequence analysis of the Rubisco activase gene revealed single nucleotide polymorphisms that could relate to this difference. The results show a potential route for selection of cultivars with increased photosynthetic efficiency in fluctuating light.

Calcium ion (Ca 2+ ) is an important second messenger that regulates numerous cellular functions. Intracellular Ca 2+ concentration ([Ca 2+ ]i) is strictly controlled by Ca 2+ channels and pumps on the endoplasmic reticulum (ER) and plasma membranes. The ER calcium pump, sarco/endoplasmic reticulum calcium ATPase (SERCA), imports Ca 2+ from the cytosol into the ER in an ATPase activitydependent manner. The activity of SERCA2b, the ubiquitous isoform of SERCA, is negatively regulated by disulfide bond formation between two luminal cysteines. Here, we show that ERdj5, a mammalian ER disulfide reductase, which we reported to be involved in the ER-associated degradation of misfolded proteins, activates the pump function of SERCA2b by reducing its luminal disulfide bond.

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